Embossing apparatus



Jan. 29, 1963 w. K. MATHEws ETAL 3,075,435

EMBossING APPARATUS Filed May 8, 1961 4 sheets-sheet 1 40 255.191. V--U-E i` -Y 144 @q f" l II 3? 283 @i INVENTOR. W/LL/AM h'. MAT/6W5 BY PON/ILD M. WROB Jan. 29, 1963 w. K. MATHEws ETAL 3,075,435

EMBOSSING APPARATUS Filed May 8, 1961 4 Sheets-Sheej; 2

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EMBOSSING APPARATUS Filed May 8, 1961 4 Sheets-Sheet I5 el l 97 i H3 il le 8191 @w "2 w 6 23 l5 m A f 27 76 52H Z2 //////W "l"v l/ M 4" o f' 2 7I 38 @j a5 m/VENTQR/y 29 w/L/AM H. M4N/w15 BY Ron/ALD M. wma

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Jan. 29, 1963 w. K. MATHEws ETAL 3,075,435

EMBossING APPARATUS Filed May 8, 1961 4 Sheets-Sheet 4 (w f l e A L )3 46 Lf' 145 |48 ,55 47 \55 154 165 154 M150 'G5 Wi 121 126 y ,Z7 |25 ne 124 [ZO EIl? INVENTOR.

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United States Patent Oce Patented Jan. 29, 1963 of Missouri Filed May 8, 1961, Ser. No. 108,341 3 Claims. (Cl. 93--73) This invention relates to high speed embossing apparatus particularly adapted to operate in conjunction with modern high speed envelope making machines, and more particularly to such apparatus which does not interfere with the normal operation of such machines.

Heretofore, various devices have been used to emboss envelopes and at various stages in their manufacture, rowever, such devices either necessitated a time consuming additional production step apart from the folding and gumming of the envelope blanks or, when used on an envelope folding machine, required slowing of the machine and often produced a low quality embossment.

it is the principal objects of the present invention to provide an embossing apparatus for use on high speed envelope making machines which produces ,a high quality embossment on the envelope blanks without interfering with the normal operation of the machines; to provide such apparatus which is quickly and easily assembled with modern high speed envelope making machines; to provide such apparatus which permits the unobstructed passage of non-embossed envelopes through the envelope making machine; to provide an embossing device which permits the envelope making machine to be adjusted in the normal manner for different sized envelope blanks without interference therewith; to provide an embosser which cycles at extremely high speed whereby the embossing operation can be completed during a normal slight pause in envelope blank motion occurring irnmediately prior to contact of the blank with the folding punch; to provide such an embossing device which produces a high quality embossment free of tears or unsightly paper stretching, which is simple and inexpensive to build and which is rugged and reliable in use.

Other obiects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings wherein are set forth by way of illustration and example certain embodiments of this invention.

FlG. 1 is a fragmentary view in side elevation showing a portion of the folding station of a high speed envelope making machine with the embossing apparatus assembled therewith.

FIG. 2 is a sectional view through the folding punch and plunger taken on the line 2 2, FiG. l, and showing the apparatus in plan.

FiG. 3 is a perspective view on an enlarged scale showing the male die supporting structure .and front transverse fold bar.

FIG. 4 is a fragmentary perspective view with parts roken away showing the rotary timing switches and the electrical power supply.

FiG. 5 is a fragmentary sectional view taken on the line 5 5, of FGURE 3, showing the embossing members and reciprocating closure apparatus therefor.

FG. 6 is a side elevation on an enlarged scale showing a rotary switch with the cover therefor removed.

PEG. 7 is a fragmentary view in side elevation on an enlarged scale showing the folding punch entering the folding die with an envelope blank therebetween.

FG. 8 is a perspective view of a finished engraved envelope.

PEG. 9 is a sectional view on an enlarged scale taken on the line 9-9, of FIGURE l, showing the fold punch guiding linkage.

PIG. l is a schematic circuit diagram showing the electrical control circuit of the embossing apparatus.

Referring to the drawings more in detail:

The Envelope Making Machine "the reference numeral 1 indicates generally an envelope blank folding station or portion of a high speed envelope making machine having an elongated frame 2 adapted to rotatably support pulleys 3 and 4 in a manner described hereinafter. A pair of longitudinally extending, parallel, laterally spaced endless conveyor belts and 6 are engaged and driven by the pulleys 3 and 4 respectively, the belts 5 and r6 being adapted to transport envelope blanks, such as blank 7, in spaced relation and in a horizontal plane indicated at 8 along a path 9 having opposite lateral edges indicated at 16 and 11 corresponding to the outer edges of the conveyor belts 5 and 6.

A pair of spaced longitudinal fold bars 12 and 13 extend parallel to the belts 5 and 6 and are positioned respectively adjacent thereto on the under side thereof. A front transverse member or fold bar 14 and a rear transverse member or fold bar 15 are secured to the frame 2 by bolts 16. The transverse fold bars 14 and 15 are parallel and spaced from each other and extend transversely of the frame 2 beyond the edges 10 and 11 of the path 9. The transverse fold bars 14 and 1S respectively intersect the longitudinal fold bars 12 and 13 at right .angles to form a rectangular folding die 17 closelv positioned beneath the plane S and opening upwardly substantially between the belts 5 and 6.

A pair of elongated rails 18 and 19 respectively extend longitudinally of the frame 2 and are spaced slightly above the belts 5 and 6 adjacent the edges iti and 11. The rails 18 and 19 support rollers, such as indicated at Ztl and 21, adapted to urge the blanks 7 into contact with the belts 5 and 6 to produce a driving engagement therewith.

A folding punch 22 adapted to mate with the rectangular folding die 17 is rigidly secured by means of a pin 23 to the lower end 2d of a vertical plunger 25. The

iunger 25' is slidably supported in a bearing 26 retained in a frame cross member 27 which extends transversely of the frame 2 above the rectangular folding die 17 (PEG. l). The frame cross member 27 is secured to the frame 2 by bolts 27'. An arm 2S in the form of an elbow or right .angle is rigidiy secured at one end thereof by means of a shaft clamp 29 to the upper portion 3@ of the plunger 25. The arm 23 terminates at the other end in an enlarged follower or head portion 31 adapted to be slidably received in a vertically extending elongated guide 32 which cooperates with the arm 2S. A link 33 is pivotally connected at one end thereof to the arm 2S adjacent the clamp 29 and at the other end thereof to the free end 34 of an arm 35. The other end of the arm 35 is xed at one end 36 of a shaft 37 which is pivotally mounted in suitable bearings 38 carried by extensions 39 of the frame cross member 27.

A link dit is rigidly connected at one end thereof to the other end 41 of the shaft 37. The link #itl has the other end pivotally connected to the upper end of a vertically extending draw bar d2 (FG. l) which is pivotally connected tat the lower end thereof to an arm i3 fixed to a shaft d4 rotatably mounted on the frame 2. A slotted arm 45 is also secured to the shaft 44 and is adapted to be reciproeably driven with a piu d6 secured to a rotatable sprocket wheel 47.

The reciprocal motion of the slotted arm vertically reciprooally drives the draw bar l2 which urges the link du in a reciprocal arcuate path which partially rotates the shaft 37. The motion of the. shaft 37 urges the arm 3S in a reciprocal arcuate path similar to that of the link di) but traversing a greater distance due to the greater length thereof. The arm 35 in turn urges the plunger 25 in a vertical, reciprocal motion with the link 33 and arm 28, the guide 32 cooperating with the arm 28 to prevent rotary moti-on of the plunger 25 during its vertical transverse.

The bearing 26 maintains the plunger 25 in a path whereby the folding punch 22 -is always in yalignment with the rectangular folding die 17. In folding the blank 7 the folding punch 22 reciprocates into the rectangular folding die 17 with the blank 7 positioned therebetween, as indicated in FIGURE 7. The 'folding punch 22 urges the bottom flap 4S, -side flaps 49 and Sii and top flap 51 to fold with respect to the body portion 52 of the envelope. The blank 7, .after passing through the die 17 is urged downwardly by the folding punch 22 into engagement with grasping fingers (not shown) for further processing in a `conventional manner.

The reciprocal motion of the folding punch 22 is maintained 4in timed relation to the motion `of the belts 5 `and 6 -by apparatus to be now described. A main drive shaft 53 driven by conventional `motive means (not shown) rotates sprocket wheels 54 and 55 fixed thereto in the direction indicated by the arrow 54 on the sprocket Wheel 54. The sprocket wheel 55 carries a drive chain 56 meshed therewith which in turn meshe-s with a sprocket wheel 57 secured to shaft 5S rotatably mounted on the frame 2. The shaft 58 has xed thereto a suitable geared wheel 49 meshing with a geared wheel 6d fixed to a rotatable shaft 61 which supports and drives the pulleys 3 and 4 to motivate the belts 5 and 6 Iin the direction indicated by the arrow 61. The shaft 61 is rotatably supported by means of suitable extensions 62 and 63 secured to the frame 2 and containing bearings 64 and 65.

As the main drive shaft 53 rotates it also rotates the sprocket wheel 54 which carries a driving chain 66 rneshed therewith and also meshed with the sprocket wheel 47 driving the slotted arm 45. It is apparent that the drive apparatus just described produces a time yor synchronized relationship between the vertical reciprocation of the folding punch 22 and the motion of the belts 5 and 6 for bringing the blanks 7 into position over the die 17 for folding.

The blanks 7 are positioned in driving engagement with the belts 5 and 6 and in suitably spaced and timed relation thereon -by means of conventional apparatus (not shown) associated with the machine 1 upstream from the direction of travel of the belts and 6. Conventional apparatus (not shown), also suitably timed and cooperating upstream with the belts 5 and 6 applies wet adhesive gum strips 67 on the bottom llap d3 and wet adhesive gum lstrips 68 on the top iiap 51. The gum strips 67 and 68 remain in a wet or sticky condition as the blank passes through the folding die 17, but subsequently dry to provide closure for the envelope between the bottom ap 43 and side aps 49 and 5d and to provide a seal-able top flap 51.

immediately prior to the descent of the folding punch 22, the blank 7 contacts a pair of stop members 69 and 79 which stop the blank as it travels downstream on the belts 5 and 6 and positions same in proper relation t-o the folding die 17 and embossing apparatus described hereinafter.

The Embossing Apparatus The embossing apparatus for use With the above described envelope making machine comprises an embossing matrix 71 which is integral with the front transverse fold bar 1d. The embossing matrix 71 has an engraved lrecess 72 facing upwardly toward the plane and in the form of the desired embossment 73 Vto be placed on the envelope blanks 7. A pair or upright posts 7d and 75 are secured at the lower ends 76 and 77 thereof to the front transverse fold bar 14 at positions respectively spaced outwardly of the edges lil and 11 of the path 9, the posts 74 and 75 having the belts 5 and 6 running therebetween. A vcross bar 7S is secured to the posts 7d and 75 at the upper ends 79 and Sil thereof by means of screws 79I and pins 8G a-bove the path 9 in spaced opposed relation to the front transverse fold bar 14 (FIG. 3).

An enlarged portion 81 located between the ends of the cross bar 78 contains a vertical cylindrical bore 82 and `forms a vertically extending air cylinder designated 83 which is integral with the cross bar 78. The air cylinder 33 is closed at the upper terminus or top 84 thereof with a cap b5 having a downwardly opening recess 86 the-rein. The cap S5 is secured to the cross bar 78 by means of suitable screws 87. The recess 86 contains a bumper 88 secured by -a suitable adhesive or the like to the underside of the top wall S9 of the cap S5. The lbumper 83 is generally of smaller size o-r diameter than the recess S6 forming passageways 94) in the cap S5 to permit air to pass into and out of the air cylinder 83 through a threaded air port 91 in the cap S5. The air port 91 is located adjacent the 4top S4 of the air cylinder 83. An air conducting tube 92 is retained lin operative communication with the air port 91 by means of Ia suitable threaded tu-be coupling 93.

A piston 94 is contained in the cylinder 8-3 and is adapted to vertically reciprocate downwardly in response to the introduction of `air under pressure into the cylinder 83 through the port 91. A hel-ical coil spring 95 is located adjacent the lower terminus or end 96 of the cylinder 83 and is adapted to resiliently urge the piston 94 upwardly. An air -bleed port 97 communicates with the lower end 96 of the cylinder S3 to permit air t-o quickly exit therefrom on the downward stroke of the piston 94.

A male die 98 having embossing projections 99 extending downwardly therefrom is rigidly secured to a vertically extending piston rod lill) at the lower end 101 thereof by means of a suitable pin 102. The upper end 103 of the piston rod 100 is rigidly secured to a boss 194 integral with the piston 94 by means of a suitable pin 105. Spaced leader o1- guide pins 1% are rigidly secured to the male die 98 with suitable pins 107 and are adapted to vertically slide in spaced vertically extending guide bearings 108 retained in the cross bar 78. The guide pins 1% and piston rod 100 align the embossing projections on the male die 96y with the engraved recess 72 for reciprocation thereinto upon introduction of air into the cylinder 83.

An air conducting tube 109 extends downwardly through the cross bar 78 and is secured thereto by means of solder or the like 110. The tube 109 terminates at the lower end 111 thereof in a pair of horizontal branch tubes 112, which respectively extend adjacent opposite sides of the male die 98 and are respectively bent downwardly to form downwardly exhausting nozzles 113. The nozzles 113 are adapted to direct streams of air toward the embossing matrix 71 for a purpose which Will become apparent hereinafter.

The air tubes 92 and 109 are each fed by an air supply tube 114. The tube 114 contains air under a high pressure for example, pounds per square inch, and has a shunt tube 115 connected thereto which shunts high pressure to a two-Way solenoid actuated air valve 116 from which the air is directed into the air conducting tube 169. The air for feeding the air conducting tube 92, however, passes through a variable air pressure regulator 117 into a manifold pipe 118 from which it enters three-Way solenoid operated air valves 119, 120 and 121 operatively connected in parallel between the manifold pipe 118 and a receiving manifold pipe 122. The manifold pipe 112 feeds into the air conducting tube 92 to reciprocate the air cylinder piston 9d, as noted above. The three-way valves 119, 121By and 121 are operatively connected in parallel across the manifold pipes 118 and 122 to provide a reasonably large orifice area across which air can flow without sacrificing the needed high speed operation under high pressure inherent in small solenoid operated valves. The valves 116, 119', 121i and 121 are rated at 24 volts DC. The air entering the manifold pipe 118 carries a small amount of oil therewith supplied by an oiler 123 located downstream from the regulator to lubricate the contacting surfaces between the piston 94 and cylindrical bore S2. The air pressure regulator 117 permits control over the epth of the embossment.

The two-way solenoid actuated air valve 116 has a pair of electrical terminals 124 and 125 for introducing electrical current into the solenoid contained therein (not shown) for operating the valve in a well known manner whereby when the two-way valve 116 is energized or actuated air ows therethrough under high pressure into the air conducting tube 109 and when the two-way sclenoid valve 116 is not actuated the valve automatically closes and the iiow therethrough stops. The three-way valves 119, 121) and 121 each have a pair of electrical terminals 126 and 127 which are respectively electrically connected in parallel as indicated in the circuit diagram of FIGURE l0. When the three-way valves 119, 120i and 121 are energized or actuated the air in the manifold pipe 118, which is at a pressure substantially equal to or lower than the pressure in the supply tube 114 as determined by the air regulator 117, ows therethrough into the manifold pipe 122, as noted above. However, when the three-way valves 119, 120 and 121 are not energized, the flow from the manifold pipe 118 therethrough not only stops but the air in the manifold pipe 122, which is maintained under pressure by the helical coil spring 95 acting against the piston 94, is allowed to exhaust through ports 123 in the three-way valves to permit a rapid return stroke of the piston 94.

A source of D.C. potential electricity to operate the valves 116, 119, 120 and 121 is provided by means of a full wave selenium rectifier 129 contained in a suitable box 131: secured to the frame 2 and having an electrical cord or power line 131 extending from a cord anchor 132 for connection to a source of common electrical power 133 such as 120 volt 60 cycle A.C. D.C. power is needed to prevent the variations in valve cycle time accompanying the actuation of the valves during variable positions on the 60 cycle A.C. potential curve. The box 130 contains a pair of transformers 134 having their primary coils 135 connected in parallel across the power line 131 but the secondary coils 136 connected in series. The transformers are adapted to reduce the voltage across both secondary coils to approximately 50 volts A.C. The secondary coils 156 feed the input terminals 135 and 139 of the selenium rectifier 129 in a well-known manner to produce approximately 50 volts DC. power in the form of full-wave rectified A.C. A filter in the form of a capacitor 137 is connected across the output terminals 1411 and 141 of the rectifier 133 to reduce the cycler variation of the DC. power in a well 1Known manner. A 50 volt potential instead of the rated 24 is used to provide faster than normal actuation of the solenoid valves, since the above-rated voltage builds up the solenoid current at an abnormally fast rate. The cycle of operation of the valves, however, is completed before rated current capacity of the solenoid is exceeded, so no damage is sustained by the valves.

The output terminal 141 is connected to the terminal 125 of the two-way air valve 116. The terminal 141 is also connected through a switch 142 to the terminals 126 of the three-way valves 111, 129 and 121 which are interconnected to provide a parallel circuit therethrough, as noted above. The switch 15132, as well as a master switch 143 is conveniently mounted on the box 13@ (FIG. l). A suitable fuze 144 is connected in the power line 131 and is mounted in a convenient position on the box 13b to interrupt the circuit in case of electrical overload.

The terminal 140 of the selenium rectifier 129 is connected to the terminals 145 and 146 which are respectively inputs to rotary switches 147 and 14S described hereinafter. The output terminal 149 of the rotary switch 147 is connected to the terminal 124 of the two-way valve 116. The output terminal d of the rotary switch 14? 6 is connected to the terminals 126 of the three-way valves 119, 12@ and 121.

The -switches 147 and 145 respectively have actuating Shafts 151 and 152 rotatably mounted on a supporting frame 153 suitably `secured to the frame 2. The shafts 151 and 152 each carry secured to one end thereof by means of a screw 154, extending axially thereinto, a rotary cam 155 (FG. 6). e switches 147 and 143 also each contain a switch assembly 156 comprising a stationary arm 157 and a pivotally movable arm 158. Each switch assembly is retained on a plate 159 by means of screws 160. Each plate 159, switch assembly 156 and rotary cam 155 are contained within a housing 161 which is normally covered by means of a removable cap 162 (FIG. 4).

The movable arms 158 each include fixed thereto, a cam follower' 163 which is maintained in contact with the face of the cam 155 by means of a leaf spring 164. Upon rotation of the cam 155, contacts 165 secured to the arms 157 and 158 periodically alternate between a contacting and a non-contacting position.

The terminals 146 and 150 described above with respect to the switch 148 are noted in FIGURE 6 and correspond to terminals 145 and 149 of switch 147. The switches 147 and 148 are identical in construction. The terminals 1426 and 15@ are electrically connected respectively to the movable arm 158 with a lead wire 166 and the stationary arm 157 with a lead wire 167. r1`he lead wire 167 is `secured to the housing 161 by means of a screw 168 and completes an electrical path to the terminal 151B through the housing 161. The wire 166 is insulated and isolated from the wire 167.

The piate 159 is free to rotate through a small angle about the cam 155 and carry the switch assembly 156 therewith, such rotation being retarded with a pair of helical springs 169 rotatively urging the plate 159 against a hoo-lc portion 17d of a retaining or adjusting rod 171. The rod 171 is maintained in adjustably fixed relation with respect to the housing 161 by means of la conical washer 172 engaging the housing 161 on one side of said washer 172 and a nut 173 on the other side thereof threadedly engaged with the rod 171. The terminal 15@ is physically and electrically secured in place between the nut 173 and a nut 174, also threadedly engaged with the rod 171, by rotating the nut 173 until the terminal is trapped (11G. 6). When the relative position of the rod 171 is changed with respect to the housing 161, the change is reflected in a slight angular displacement of the plate 159 which in turn changes the timing relationship between the cam 155 and cam follower lt is apparent that the switches 147 and 148 are respectively adapted to adjustably periodically close and open an electrical path therethrough in response to the rotation o-f the actuating shafts 151 and 152. Sprocket wheels 175 and 176 are respectively secured to the shafts 151 and 152 and together carry a timing chain 177 mashed therewith, the timing chain 177 also meshing with a sprocket wheel 178 secured to the shaft 58, whereby synchronization is achieved between the main rotary drive shaft 47 of the envelope making machine and the timing of the actuation of the air valves 116, 119, 129 and 121. The sprocket wheels 175, 176 and 178 are partially covered with a housing 179 suitably secured to the frame 2.

The rotary switch 143 is adjusted to close and thereby actuates the valves 119, 121i and 121 at the instant when the blank 7 is positioned over the folding die 17, and open before the folding punch 22 reciprocates thereinto. The rotary switch 147, on the other hand, is adjusted to close and thereby actuate the air valve 116 when the male die 98 begins to separate from the embossing matrix 71 and open when the top ap 51 clears the front transverse fold bar 14.

In operation, an envelope blank 7 travels downstream viththe conveyor belts 5 and 6 until the motion of the blank is abruptly stopped over the folding die 17 by contacting the stop members 69 and 70. As the blank '7 reaches this stopping position, the top 'flap 51 is autoniatically centered by the stop members o9 and 7d in engraving position beneath the male die 93. The air valves 119, 129 and 121 are actuated at this instant, or slightly prior thereto, by the rotary switch 14S to introduce air under pressure into the air cylinder S3 which reciprocates the male die 98 against the embossing matrix 71 with the flap 51 therebetween, embossing same. The air valves 119, 12b and 121 are then immediately deaetu-ated by the continued rotation of the cam 155 in the switch 14S permitting the air above the piston g3 to exhaust out of the ports 12S and allowing the helical spring 95 to urge the male die out of contact with the top flap S1. As the male die 9S begins to separate from lthe top flap S1, the rotary switch 147 actuates the air valve 116 to permit high pressure air to exhaust from the nozzles 113 and irnpinge against the tiap 51. the same instant, the folding punch 22 reciprocates downwardly into contact with the body portion 52 ofthe blank '7. rl'he impinging air from the nozzles 113 prevents the top flap 51 from rising and contacting the male die 93 as the blank 7 is urged downwardly into the folding die 17. This prevents the sticky, gum strips 68 on the nap 51 from depositing wet gum or glue onto the male die which would eventually interfere with the operation thereof. When the top flap 51 clears the front transverse fold bar 1d the impingement of the air is no longer necessary and the rotary switch 147 deactuates the air valve 116 to stop the flow of air therethrough.

The longitudinal fold bars 12 and 13 may be laterally adjusted with respect to each other for handling dierent envelope blank sizes by rotating a shaft 180 threadedly engaged therewith. The shaft 180 has a socket 181 fixed to one end thereof and adapted to accept a suitable hand crank (not sho-wn). A sprocket wheel 182 is secured to the other end of the shaft 175 and Carries a chain 183 meshed with a similar sprocket wheel and shaft located at the other end of the longitudinal fold bar 12 and 13 I(not shown) to insure that the longitudinal fold bars remain perfectly parallel with each other during lateral adjustment. Note that the lateral adjustment of the fold bars 12 and 13 does not interfere with the placement or operation of the embossing apparatus described above. lt is apparent that a forward or rearward adjustment of the rear transverse fold bar 1S with respect to the front transverse fold bar 14 will also not interfere with the placement or operation of the embossing apparatus.

lt is to be understood that we have illustrated and described one form of our invention, it is not to be limited to the specific form or arrangement of parts herein described and sho-wn as except insofar as such limitations are included in the following claims.

Vle claim:

l. in combination with an envelope making machine having a flap folding die with a front fold bar and a folding punch adapted to periodically reciprocate thereinto to fold a wet gum stripped flap of an envelope blank and including rotary drive means for said punch; an embossing apparatus comprising an embossing matrix integral with said fold bar, a cross bar, means supporting sai-d cross bar spaced from said fold bar for receiving said fiap therebetween with the gum strip facing toward said cross bar, an air cylinder supported by said cross bar and having an air port adjacent one end thereof, a first air conducting tube communicating with said port, a pis- (con 4in said cylinder adapted tto reciprocate toward said lfold bar in response to the introduction of air under pressure into said cylinder through said port, resilient means adapted to urge said piston away from said fold bar, a male die, a piston rod extending between and secured to said male die and said piston, means aligning said male die lwith said matrix for reciprocation thcreinto, a second air conducting tube terminating in at least one air exhaustin. nozzle, said nozzle being adapted to direct a stream of air toward said fold bar to slidably urge Said flap toward said fold bar, a source of air under pressure, a solenoid actuated air valve operatively connected between said air source and said second air conducting tube, at least one three-way solenoid actuated air valve, said three-way air valve being operatively connected between said first air conducting tube and said air source, a source of D C. potential electricity connected to said solenoid valves, a first and a second rotary switchV respectively connected between said electricity source and said solenoid actuated air valves for respectively controllingsame, said first and second switches each having a rotary actuating shaft and being adapted to adjustably periodically close and open an electrical Vpath therethrough in response to the rotation of said actuating shafts, and means driving and synchronizing said actuating shafts with said `rotary Ydrive means for maintaining said switches in mutually timed relation with the reciprocation of said folding punch, said first switch being adjusted to close when the blank is positioned over said folding die and open before said vpunch reciprocates into said folding die, saidsecond switch being adjusted to close when said male die begins to separate from said matrix and open when the fiap clears said fold bar whereby after embossing the flap is drawn across said fold bar into said die` without gum depositing contact.

2. In combination lwith an envelope making machine having a flap folding die with a fold bar, said machine having a folding punch `adapted to reciprocate into said folding die to fold a Wet gum stripped flap of an envelope blank by cooperating with said fold bar, and including drive means for said punch; an embossing apparatus comprising an embossing matrix associated with said fold bar, a cross bar, means supporting said cross bar spaced from said fold bar for receiving said flap therebetween with the gum strip facing toward said cross bar, reciprocating means supported by said cross bar, a rnale die secured to said reciprocating means and aligned with said matrix for reciprocation thereinto, an air conducting tube terminating in at least one air exhausting nozzle, said nozzle being adapted to direct a stream of air toward said fold bar to slidably urge said flap towardv said fold bar, a source of air under pressure, said air source being connected to said air conducting tube, and means operating said reciprocating means in timed relation with said punch ldrive means whereby after embossing the flap is drawn across said fold bar into sai-d die without gum depositing contact.

3. The combination of claim 2 including an air valve operatively connected between said air source and said air conducting tube, and means alternately opening and closing said valve in timed relation with said punch drive means whereby said stream of air is directed toward the flap only during flap folding.

References Cited in the file of this patent UNlTED STATES PATENTS 5411685 Tate et al Sept. 24, 1895 1,177,222 Acly et al Mar. 28, 1916 1,929,703 McDonough Oct. l0, i933 2,646,746 Muller luly 28, 1953 

1. IN COMBINATION WITH AN ENVELOPE MAKING MACHINE HAVING A FLAP FOLDING DIE WITH A FRONT FOLD BAR AND A FOLDING PUNCH ADAPTED TO PERIODICALLY RECIPROCATE THEREINTO TO FOLD A WET GUM STRIPPED FLAP OF AN ENVELOPE BLANK AND INCLUDING ROTARY DRIVE MEANS FOR SAID PUNCH; AN EMBOSSING APPARATUS COMPRISING AN EMBOSSING MATRIX INTEGRAL WITH SAID FOLD BAR, A CROSS BAR, MEANS SUPPORTING SAID CROSS BAR SPACED FROM SAID FOLD BAR FOR RECEIVING SAID FLAP THEREBETWEEN WITH THE GUM STRIP FACING TOWARD SAID CROSS BAR, AN AIR CYLINDER SUPPORTED BY SAID CROSS BAR AND HAVING AN AIR PORT ADJACENT ONE END THEREOF, A FIRST AIR CONDUCTING TUBE COMMUNICATING WITH SAID PORT, A PISTON IN SAID CYLINDER ADAPTED TO RECIPROCATE TOWARD SAID FOLD BAR IN RESPONSE TO THE INTRODUCTION OF AIR UNDER PRESSURE INTO SAID CYLINDER THROUGH SAID PORT, RESILIENT MEANS ADAPTED TO URGE SAID PISTON AWAY FROM SAID FOLD BAR, A MALE DIE, A PISTON ROD EXTENDING BETWEEN AND SECURED TO SAID MALE DIE AND SAID PISTON, MEANS ALIGNING SAID MALE DIE WITH SAID MATRIX FOR RECIPROCATION THEREINTO, A SECOND AIR CONDUCTING TUBE TERMINATING IN AT LEAST ONE AIR EXHAUSTING NOZZLE, SAID NOZZLE BEING ADAPTED TO DIRECT A STREAM OF AIR TOWARD SAID FOLD BAR TO SLIDABLY URGE SAID FLAP TOWARD SAID FOLD BAR, A SOURCE OF AIR UNDER PRESSURE, A SOLENOID ACTUATED AIR VALVE OPERATIVELY CONNECTED BETWEEN SAID AIR SOURCE AND SAID SECOND AIR CONDUCTING TUBE, AT LEAST ONE THREE-WAY SOLENOID ACTUATED AIR VALVE, SAID THREE-WAY AIR VALVE BEING OPERATIVELY CONNECTED BETWEEN SAID FIRST AIR CONDUCTING TUBE AND SAID AIR SOURCE, A SOURCE OF D.C. POTENTIAL ELECTRICITY CONNECTED TO SAID SOLENOID VALVES, A FIRST AND SECOND ROTARY SWITCH RESPECTIVELY CONNECTED BETWEEN SAID ELECTRICITY SOURCE AND SAID SOLENOID ACTUATED AIR VALVES FOR RESPECTIVELY CONTROLLING SAME, SAID FIRST AND SECOND SWITCHES EACH HAVING A ROTARY ACTUATING SHAFT AND BEING ADAPTED TO ADJUSTABLY PERIODICALLY CLOSE AND OPEN AN ELECTRICAL PATH THERETHROUGH IN RESPONSE TO THE ROTATION OF SAID ACTUATING SHAFTS, AND MEANS DRIVING AND SYNCHRONIZING SAID ACTUATING SHAFTS WITH SAID ROTARY DRIVE MEANS FOR MAINTAINING SAID SWITCHES IN MUTUALLY TIMED RELATION WITH THE RECIPROCATION OF SAID FOLDING PUNCH, SAID FIRST SWITCH BEING ADJUSTED TO CLOSE WHEN THE BLANK IS POSITIONED OVER SAID FOLDING DIE AND OPEN BEFORE SAID PUNCH RECIPROCATES INTO SAID FOLDING DIE, SAID SECOND SWITCH BEING ADJUSTED TO CLOSE WHEN SAID MALE DIE BEGINS TO SEPARATE FROM SAID MATRIX AND OPEN WHEN THE FLAP CLEARS SAID FOLD BAR WHEREBY AFTER EMBOSSING THE FLAP IS DRAWN ACROSS SAID FOLD BAR INTO SAID DIE WITHOUT GUM DEPOSITING CONTACT. 